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NOTES  Ofl  THE  PIiflflTlHG  OF 


S  nil  in  OH  Ap  TROUT 


By  ^    B. 

Ot  the  California  pish  Commission. 


A  REPORT  ON  THE  PLANTING  OF  QUINNAT  SALMON 

FRY  IN  THE  SHORT  COAST  STREAMS  OF 

MARIN  COUNTY,  CALIFORNIA, 

WITH  RESULTS  OF  OBSERVATIONS  MADE  UPON  THEIR 
MOVEMENTS,  FOOD,  RATE  OF  GROWTH,  ENEMIES,  ETC. 

By  N.  B.  SCHOFIELD,  of  California  Fish  Commission. 


DESCRIPTION  OF  PLATES.  The  three  accompanying  plates  are  to  illustrate  the  rate 
of  growth  of  Quinnat  salmon  fry  from  the  streams  of  Marin  County,  California. 

In  Plate  I  are  four  outline  figures  of  the  fry  at  progressive  ages.  Fig.  1  represents 
the  young  salmon  with  yolk  sac  just  absorbed;  Fig^2^25  days  after  absorption  of  yolk 
sac;  Fig. JLJL6  days  after  absorption  of  yolk  sac;  Fig.^jg2  days  after  absorption 
of  yolk  sac.  Figures  1,  2,  3,  and  4  are  from  specimens  1.35,  1.7,  2.51,  and  2.98  inches, 
respectively. 

Plate  II  represents  a  young  Quinnat  salmon  taken  in  brackish  water,  107  days  after 
absorption  of  yolk  sac— showing  loss  of  markings  below  lateral  line  and  the  faded  out 
parr  marks,  caused  by  the  brackish  water.  Drawn  from  an  average  specimen  3.2  inches 
long.  This  drawing  should  be  compared  with  Plate  III,  which  figures  a  young  salmon 
from  fresh  water. 

Plate  III  shows  a  young  Quinnat  salmon  taken  in  fresh  Water  162  days  after  absorp- 
tion of  yolk  sac.  Drawn  from  an  average  specimen  3.55  inches  long. 

The  planting  of  Quinnat  salmon  fry  in  the  short  coast  streams  of 
Marin  County  was  primarily  an  experiment.  The  Quinnat  salmon  has 
never  been  known  to  spawn  in  these  streams,  probably  due  to  their 
proximity  to  the  Sacramento  River,  which  is  the  popular  spawning 
ground  for  the  salmon  of  this  region.  (North  of  the  Russian  River,  the 
Quinnat  spawns  in  the  small  streams  as  well  as  in  the  larger  rivers  of 
the  coast.) 

Paper  Mill  Creek  and  its  tributaries  are  exceptionally  rich  in  aquatic 
insect  life,  affording  an  abundance  of  food  for  the  fry;  and  the  absence 
of  predaceous  fishes,  excepting  the  trout  and  blob,  make  them  appar- 
ently better  streams  for  the  rearing  of  young  salmon  than  the  Sacra- 
mento. It  was  thought  that  if  the  fry  could  thrive  in  these  streams  and 
pass  successfully  into  salt  water,  it  would  be  of  advantage  to  utilize 
coast  hatcheries  and  plant  in  the  smaller  streams  where  the  young 
salmon  would  not  be  subjected  to  their  enemies  like  they  are  during 
the  long  journey  from  the  upper  Sacramento  to  the  sea. 

In  December,  1896,  855,000  eyed  Quinnat  salmon  eggs  were  shipped 
from  the  Battle  Creek  hatchery  to  the  Bear  Valley  hatchery  in  Marin 
County,  California.  Here  they  were  hatched  early  in  February,  1897, 
and  after  the  yolk  sacs  were  absorbed,  which  was  about  thirty  days 

23946^ 


A  REPORT  ON  THE  PLANTING  OF  QUINNAT  SALMON 

FRY  IN  THE  SHORT  COAST  STREAMS  OF 

MARIN  COUNTY,  CALIFORNIA, 

WITH  RESULTS  OF  OBSERVATIONS  MADE  UPON  THEIR 
MOVEMENTS,  FOOD,  RATE  OF  GROWTH,  ENEMIES,  ETC. 

By  N.  B.  SCHOFIELD,  of  California  Fish  Commission. 


DESCRIPTION  OF  PLATES.  The  three  accompanying  plates  are  to  illustrate  the  rate 
of  growth  of  Quinnat  salmon  fry  from  the  streams  of  Marin  County,  California. 

In  Plate  I  are  four  outline  figures  of  the  fry  at  progressive  ages.  Fig.  1  represents 
the  young  salmon  with  yolk  sac  just  absorbed;  Fig-J^Jip  days  after  absorption  of  yolk 
sac;  Fig. JL AQ  days  after  absorption  of  yolk  sac;  Fig.^j62  days  after  absorption 
of  yolk  sac.  Figures  1,  2,  3,  and  4  are  from  specimens  1.35,  1.7,  2.51,  and  2.98  inches, 
respectively. 

Plate  II  represents  a  young  Quinnat  salmon  taken  in  brackish  water,  107  days  after 
absorption  of  yolk  sac— showing  loss  of  markings  below  lateral  line  and  the  faded  out 
parr  marks,  caused  by  the  brackish  water.  Drawn  from  an  average  specimen  3.2  inches 
long.  This  drawing  should  be  compared  with  Plate  III,  which  figures  a  young  salmon 
from  fresh  water. 

Plate  III  shows  a  young  Quinnat  salmon  taken  in  fresh  Water  162  days  after  absorp- 
tion of  yolk  sac.  Drawn  from  an  average  specimen  3.55  inches  long. 

The  planting  of  Quinnat  salmon  fry  in  the  short  coast  streams  of 
Marin  County  was  primarily  an  experiment.  The  Quinnat  salmon  has 
never  been  known  to  spawn  in  these  streams,  probably  due  to  their, 
proximity  to  the  Sacramento  River,  which  is  the  popular  spawning 
ground  for  the  salmon  of  this  region.  (North  of  the  Russian  River,  the 
Quinnat  spawns  in  the  small  streams  as  well  as  in  the  larger  rivers  of 
the  coast.) 

Paper  Mill  Creek  and  its  tributaries  are  exceptionally  rich  in  aquatic 
insect  life,  affording  an  abundance  of  food  for  the  fry;  and  the  absence 
of  predaceous  fishes,  excepting  the  trout  and'  blob,  make  them  appar- 
ently better  streams  for  the  rearing  of  young  salmon  than  the  Sacra- 
mento. It  was  thought  that  if  the  fry  could  thrive  in  these  streams  and 
pass  successfully  into  salt  water,  it  would  be  of  advantage  to  utilize 
coast  hatcheries  and  plant  in  the  smaller  streams  where  the  young 
salmon  would  not  be  subjected  to  their  enemies  like  they  are  during 
the  long  journey  from  the  upper  Sacramento  to  the  sea. 

In  December,  1896,  855,000  eyed  Quinnat  salmon  eggs  were  shipped 
from  the  Battle  Creek  hatchery  to  the  Bear  Valley  hatchery  in  Marin 
County,  California.  Here  they  were  hatched  early  in  February,  1897, 
and  after  the  yolk  sacs  were  absorbed,  which  was  about  thirty  days 

239462 


later,  they  were  fed  lor  a  few  days  on  curds  of  milk,  and  then,  in  tl 
second  week  of  March,  were  turned  into  Paper  Mill  Creek  and  its  trib 
taries — Nicasio,  Olema,  and  Hatchery  creeks.     The  fry  were  strong  an,, 
healthy,  and  as  the  streams  were  near  the  hatchery,  and  the  fish  were  in 
no  case  over  two  hours  in  transportation,  they  were  turned  into  the 
streams  in  the  best  of  condition. 

The  young  salmon  were  watched  day  after  day  and  systematic 
observations  made  upon  their  movements,  habits,  etc.  The  work  was 
first  begun  by  the  United  States  Fish  Commission,  and  carried  on 
until  the  middle  of  May.  After  a  break  here  of  three  weeks,  the 
California  State  Commission  carried  it  on  to  completion. 

The  thing  to  be  feared  in  this  experiment  was  that  the  streams 
would  prove  too  short  and  that  the  young  salmon  would  arrive  at  salt 
water  before  they  were  ready  to  conform  to  the  kind  of  life  they  would 
have  to  lead  there. 

The  observations  carried  on  in  connection  with  the  fate  of  these 
young  salmon  fully  demonstrate  the  success  of  the  experiment  and 
prove  that  the  fry  can  be  as  safely  planted  in  these  streams  as  in  the 
Sacramento.  They  grew  more  rapidly  than  the  same  fry  in  the  Sacra- 
mento, had  fewer  enemies,  and  passed  successfully  into  salt  water  and 
thrived  there. 

By  far  the  most  interesting  part  of  the  experiment  was  the  knowledge 
gained  as  to  the  habits,  enemies,  and  growth  of  the  fry  after  being 
turned  loose.  The  streams  being  free  from  any  young  salmon  but  those 
planted  from  the  hatchery,  an  excellent  opportunity  to  observe  the  rate 
of  growth  was  afforded.  Any  knowledge  in  this  line  is  of  great 
economic  importance,  as  it  enables  us  to  more  intelligently  choose  the 
right  time  and  place  to  plant  the  fry,  and  proves  that  they  do  not 
require  two  or  even  three  years  to  reach  salt  water. 

Paper   Mill  Creek,  the  largest  stream  in  Marin  County, 

DESCRIP-     rises  in  the  high  land  just  north  of  Golden  Gate,  and  runs 

TION  OF      northwest  for  about  twenty-five  miles,  where  it  empties 

STREAMS,  into  Tomales  Bay  after  passing  through  a  three-mile 
stretch  of  tide  water.  The  bay  continues  a  very  narrow 
stretch  of  water  in  the  same  northwesterly  direction  for  thirty  miles 
before  the  open  sea  is  reached.  Paper  .Mill  Creek  is  formed  by  the 
junction  of  the  San  Geronimo  and  Lagunitas,  each  of  which  is  quite 
small,  the  water  cold  and  swift,  running  over  a  rough  rocky  bottom,  and 
everywhere  overhung  with  trees  and  bushes.  After  uniting  to  form  the 
main  stream,  the  water  frequently  runs  over  quiet  stretches  of  gravelly 
bottom,  but  for  the  most  part  the  bed  is  rough  and  rocky  and  there  are 
many  cascades  and  deep  rocky  pools.  The  stream  for  nearly  its  entire 
length  is  well  shaded  with  overhanging  trees.  The  width  of  the  stream 
in  its  normal  state  is  about  fifty  feet,  and  its  depth  averages  about 


FIG.  1. 


FIG.  2. 


FIG.  4. 
PLATE  I— SALMON  FRY. 


feet,  but  its  size  is  increased  enormously  after  each  heavy  rain.  The 
water  in  the  upper  end  of  Paper  Mill  Creek  during  the  six  months  after 
planting  the  fry  had  an  average  maximuna  temperature  of  64°,  while 
at  the  lower  end  in  tide  water  the  average  was  71°. 

Nicasio  Creek  rises  to  the  east  of  Paper  Mill  Creek,  and  flows  into  it 
about  five  miles  above  tide  water.  Nicasio  Creek  is  very  much  smaller 
than  the  Paper  Mill,  being  only  about  twenty  feet  wide,  with  an  average 
depth  of  six  inches.  Throughout  its  length  it  flows  over  flat,  gravelly 
beds,  with  few  trees  or  bushes  to  shade  the  water.  The  sun  has  full 
sweep  at  it  and  heats  the  water  each  day  during  the  summer  to  a  tem- 
perature of  75°  or  80°. 

Olema  and  Hatchery  creeks  rise  to  the  west  of  the  main  Paper  Mill, 
and  flow  almost  parallel  to  it,  emptying  into  it  near  together  about  one 
mile  below  upper  tide-water  mark.  Olema  Creek  is  about  the  size  of 
Nicasio,  but  carries  more  water  during  the  dry  season.  The  water,  too, 
is  much  cooler,  and  the  upper  stream  has  more  of  the  character  of  the 
upper  Paper  Mill.  The  banks  are  thickly  grown  with  brush  and  trees. 
The  last  two  miles  of  the  creek  runs  through  low  swampy  land,  with 
its  banks  most  of  the  way  heavily  .lined  with  willows.  The  average 
maximum  temperature  for  lower  Olema  was  63°,  and  the  upper  stream 
averaged  but  one  degree  colder. 

Hatchery  Creek  is  very  much  smaller  than  Olema  Creek,  and  is  not 
nearly  so  long.  At  first  fed  by  springs  and  running  through  cool, 
shady  woods,  the  water  is  quite  cold,  but  on  gaining  the  open  valley  and 
running  through  two  miles  of  marshy  lowlands,  with  but  little  shade, 
it  becomes,  on  reaching  Paper  Mill  Creek,  even  warmer  than  the  water 
in  Olema  Creek.  The  average  maximum  temperature  of  the  upper 
Hatchery  Creek  was  54°,  while  at  the  lower  end  the  average  was  64°. 

The  species  of  fish  found  in  these  streams  are  limited  to  four.  The 
most  important  is  the  steelhead  (Salmo  gairdneri),  which  runs  in  from 
salt  water  each  winter  and  spawns  in  the  streams,  keeping  them  well 
stocked  with  young  trout.  About  the  most  abundant  fish  is  the  "chub" 
(Rutilus  symmetricus) .  The  "stickle-back"  (Gasterosteus  cataphractus) 
and  "blob"  (Coitus  gulosas)  are  fairly  abundant.  Occasionally  the  dog 
salmon  (Oncorhynchus  keta)  enters  these  streams  and  spawns. 

Tomales  Bay,  nowhere  deep,  grows  very  shallow  at  its  upper  end, 
where  it  receives  Paper  Mill  Creek.  No  bar  ever  forms  across  the  mouth 
of  the  creek,  as  is  the  case  in  most  of  the  small  coast  streams,  but  is 
always  open  for  fish  to  run  either  in  or  out.  Temperature  of  Tomales 
Bay  at  its  upper  end  averaged  70°. 


The  young  salmon  at  the  time  they  were  turned  loose  had 
THE  PLANT-  an  average  length  of  1.35  inches.  On  being  liberated 

ING  OF  from  the  cans  they  scattered  in  all  directions,  the  swift 
THE  FRY.  current  at  first  carrying  them  some  distance  down  stream. 
But  they  soon  recovered,  and  turned  their  heads  against 
the  strong  current,  and  found  their  way  immediately  to  the  quieter 
waters  along  the  shallow  edges,  in  eddies,  quiet  pools,  or  among  the 
stones  at  the  bottom  of  the  stream.  Some  few  would  even  move  a  few 
yards  up  stream,  and  demonstrated  that  they  were  able  to  hold  their 
own  even  against  a  very  swift  current.  On  gaining  quieter  waters  they 
rested  themselves,  moving  only  enough  to  keep  from  drifting  down 
stream.  As  soon  as  they  gained  a  position  of  this  kind  they  imme- 
diately began  feeding  on  any  particles  of  food  that  floated  within  their 
sight;  often  snapping  viciously  at  flies  half  as  large  as  themselves. 
Each  individual  acts  for  himself.  They  do  not  run  in  schools,  and  no 
more  than  two  or  three  are  found  together  unless  the  nature  of  the 
stream  compels  it.  In  eddies  and  pools  they  are  thrown  together,  but 
in  a  long,  shallow,  quiet  stretch  of  water  they  scatter  out — each  one 
taking  a  position  in  the  eddy  of  a  small  stone,  or  other  object,  where 
they  have  to  barely  move  a  fin  to  keep  their  position,  while  the  water 
above  them  is  moving  swiftly.  Lying  in  such  places  they  watch  for 
insects  or  any  particles  of  food  that  may  be  floating  past.  They  feed 
principally  upon  objects  floating  on  the  surface,  but  often  they  are  seen 
to  strike  at  objects  beneath.  After  striking  at  an  object  they  almost 
invariably  return  to  their  old  position.  Frequently  one  would  be  seen 
to  move  a  few  yards  down  stream  and  take  up  another  similar  position. 
The  young  salmon  undoubtedly  move  down  stream  in  this  manner: 
moving  down  individually  and  by  dropping  a-few  feet  at  a  time. 

After  two  weeks  in  the  stream  but  very  few  of  them  were  to  be  found 
in  the  shallow  water;  nearly  all  had  moved  into  the  deeper  holes.  Here 
they  would  be  nearer  the  center  of  the  current,  where  there  is  more 
floating  food  and  where  they  could  also  hide,  for  by  this  time  they  are 
very  shy,  and  dart  into  the  deeper  water  or  under  a  rock  at  one's 
approach.  The  young  steelheads  which  hatched  out  shortly  after  this 
time  were  not  nearly  so  shy  at  the  same  age. 

Four  weeks  after  planting,  practically  all  had  moved  into  the  deeper 
holes,  and  as  long  as  they  remained  in  the  streams  they  occupied  these 
places.  In  the  deep  water  of  the  lower  Paper  Mill,  where  the  water  was 
four  and  five  feet  deep,  they  would  hang  stationary  in  the  center  of  the 
current  a  foot  or  two  below  the  surface,  darting  now  and  then  at  objects 
on  the  surface. 


As   before   stated,  the   only   noticeable   movement   c. 
MOVEMENT     stream  was  the  occasional  movement  of  individuals  drop- 
DOWN         ping  from  one  resting  place  to^  another.     During  the  first 

STREAM.  three  weeks  after  planting,  the  water  in  the  streams  was 
high  and  muddy,  and,  except  in  Hatchery  Creek,  good 
observations  could  not  be  made.  It  was  only  a  matter  of  a  couple  of 
days  until  most  of  the  salmon  had  dropped  down  out  of  the  upper 
Hatchery  Creek.  If  there  was  a  similar  movement  of  the  young  salmon 
in  the  other  streams  during  the  first  few  days  I  do  not  know;  but  when 
the  first  seining  was  done,  a  month  after  planting,  the  fry  were  found 
more  abundant  in  tide  water  than  in  the  upper  streams  where  they 
were  liberated.  There  can  be  no  doubt  that  there  was  a  decided  move- 
ment down  stream  during  the  first  month,  which  probably  began  imme- 
diately after  planting. 

Forty-five  days  after  planting,  the  fry  were  found  in  considerable 
numbers  in  brackish  water.  As  this  was  the  first  time  seining  was 
done  in  brackish  water,  we  do  not  know  how  much  sooner  they  reached 
this  point.  We  subsequently  learned  that  the  fishermen  near  Marshall, 
fifteen  miles  down  the  bay,  caught  the  young  salmon  in  considerable 
numbers  as  early  as  the  last  of  April,  or  fifty  days  after  they  were 
liberated.  At  this  time  for  about  a  week  they  caught  fifteen  or  twenty 
at  a  haul  in  their  300-foot  nets.  After  a  week  they  caught  only  two  or 
three  in  a  haul,  and  then,  as  the  fish  grew  scarcer,  they  caught  only  two 
or  three  in  a  day's  seining.  After  the  middle  of  June,  three  months 
after  planting,  they  caught  no  more. 

It  is  unfortunate  that  we  have  to  rely  solely  on  the  fishermen  for 
information  as  to  when  the  salmon  reached  salt  water.  Information 
obtained  in  this  way  cannot  usually  be  relied  upon,  but  the  young 
salmon  was  a  new  fish  in  the  bay  and  the  fishermen  could  not  help 
noticing  it.  The  stories  of  the  different  fishermen  agree  so  well  that  in 
this  case  it  is  safe  to  rely  on  them. 

The  first  seining  in  the  bay  was  on  April  29th,  fifty  days  after  plant- 
ing, on  which  day  we  caught  one  of  the  young  salmon.  This  was  at  a 
place  about  two  miles  from  the  mouth  of  Paper  Mill  Creek.  The  sein- 
ing was  done  with  a  thirty-foot  net,  and  although  we  seined  almost 
daily  in  the  bay  after  this  and  with  a  fifty-foot  net,  not  another  salmon 
was  caught. 

The  young  salmon  were  found  in  brackish  water,  near  the  mouth  of 
Paper  Mill  Creek,  up  to  the  llth  of  May,  two  months  from  the  time  of 
planting.  This  date  probably  marks  the  end  of  the  run.  Those  that 
remained,  continued  to  go  out  a  few  at  a  time,  until  by  the  sixth  month 
but  very  few  were  left  in  the  streams.  After  the  sixth  month  no  seining 
was  done  until  the  eleventh  month,  which  was  after  the  winter  rains. 
After  the  most  thorough  seining  at  this  time  only  three  of  the  fry  could  be 
found,  showing  that  practically  all  had  run  out  before  the  end  of  the  year. 


g   

By  the  middle  of  the  second  month,  when  the  water  had  become  clear 
enough  to  watch  the  young  salmon  from  the  bank,  it  was  found  that 
they  retained  their  positions  in  the  current  for  hours  without  moving 
down  stream  even  for  a  few  feet.  In  one  instance  an  albino  (one  with- 
out color)  kept  one  position  for  three  days,  after  which  it  could  not  be 
found  either  above  or  below  its  old  position.  These  facts  all  tend  to 
show  that  there  was  a  decided  movement  of  the  salmon  down  stream 
during  the  first  month,  and  after  that  time  they  moved  out  much  slower. 
It  probably  took  the  rains  of  the  next  winter  to  drive  them  all  out. 

We  tried  another  experiment.  By  stretching  a  net  across  a  narrow 
place  near  the  mouth  of  Paper  Mill  Creek  as  the  tide  was  coming  in, 
it  was  demonstrated  that  the  salmon  play  back  and  forth  with  the 
tide  before  passing  into  salt  water,  as  they  repeatedly  ran  into  the  net 
ahead  of  the  tide  when  it  was  fixed  in  this  way. 

In  all  of  the  streams  except  Hatchery  Creek  the  fry  were 

MOVEMENT     planted  where  they  could  easily  move  up  stream  two  or 

UP  three  miles  if  they  so  desired.     The  streams  were  care- 

STREAM.  fully  seined  above  the  planting  places  to  determine  to 
what  extent  they  moved  up  stream.  In  Nicasio  Creek 
only  a  very  few  had  moved  up,  and  they  had  gone  but  a  fourth  of  a 
mile  above  where  they  were  liberated.  We  found  a  few  in  Olema  Creek 
a  fourth  of  a  mile  above  where  they  were  planted.  In  Paper  Mill  Creek 
I  found  that  none  had  moved  up  stream.  All  of  the  side  streams  were 
seined  to  see  if  the  fry  had  entered  any  of  them,  but  it  was  found  that 
they  had  entered  only  one — a  very  small  stream  fed  by  springs  flowing 
into  lower  Hatchery  Creek.  The  water  in  this  small  stream  was  much 
colder  than  the  water  in  the  creek  and  was  grown  full  of  water  cress. 
Nearly  a  hundred  of  the  fry  had  entered  this  arid  were  found  as  far  up 
as  they  could  get.  Some  had  even  found  their  way  through  a  perfect 
mat  of  grass  and  drifted  rubbish.  The  current  in  this  stream  was  very 
slow,  and  it  entered  the  creek  at  such  an  angle  that  it  was  a  sort  of  trap, 
and  I  have  no  doubt  the  fry  got  in  there  in  trying  to  get  down  stream. 
Although  some  of  the  fry  do  work  up  stream  for  a  short  distance,  they 
are  the  exception.  Why  they  move  down  stream  we  do  not  know,  and 
we  will  have  to  credit  it  to  instinct.  A  young  steelhead  or  other  trout 
when  frightened  prefers  to  dart  up  stream  rather  than  down,  and  if  one 
wades  down  stream  and  attempts  to  drive  them  before  him  he  will  find 
that  they  will  not  drive,  but  will  dart  between  his  legs  or  around  him  in 
their  frantic  efforts  to  get  up  stream.  Knowing  this  trait  of  the  fish, 
in  seining  for  them  the  net  is  always  hauled  down  stream.  With  the 
salmon  fry  it  is  different — when  frightened  they  will  run  even  more 
readily  down  than  up  stream.  By  walking  along  a  small  stream  they 
can  be  driven  either  up  or  down.  In  seining  for  them  they  are  caught 
as  readily  by  seining  against  the  current  as  with  it. 


—  10  — 

The  most  important  part  of  the  work  was  finding  the  rate 

GROWTH,  of  growth  of  the  young  salmon  while  remaining  in  the 
stream.  This  was  determined  by  capturing  series  of  the 
fry  at  intervals  and  making  careful  measurements  of  their  length. 

The  young  salmon  were  put  in  the  stream  on  or  about  the  10th  of 
March,  thirty  days  after  hatching,  at  which  time  their  yolk  sacs  were 
absorbed.  At  this  time  their  average  length  was  1.35  inches,  and  the 
rate  of  growth  is  figured  from  this  time.  Although  the  rate  of  growth 
could  have  been  determined  more  accurately  had  larger  series  of  fry 
been  saved,  it  is  accurate  enough  to  demonstrate  a  remarkable  growth 
and  to  enable  us  to  make  comparisons  between  the  different  streams  and 
different  parts  of  the  same  stream.  It  also  gives  us  some  idea  what  to 
expect  in  larger  rivers. 

The  most  rapid  growth  was  during  the  first  month,  at  the  end  of 
which  time  they  had,  in  the  lower  stream,  reached  an  average  length  of 
2.28  inches;  a  gain  for  the  month  of  .93  of  an  inch.  A  few  individuals 
reached  a  length  of  2.40  inches. 

Through  the  second  month  the  growth  was  not  quite  so  great,  and 
during  the  third  and  fourth  months  correspondingly  less.  At  the  end 
of  the  second  month  the  salmon  in  the  lower  end  of  the  creeks  averaged 
2.98  inches  in  length,  and  a  few  had  reached  a  length  of  3.1  inches. 

During  these  first  two  months  the  fish  in  the  lower  streams  averaged 
considerably  larger  than  those  above.  At  the  end  of  the  first  month 
those  above  averaged  1.71  inches,  against  2.28  inches  for  those  below. 
At  the  end  of  the  second  month  those  above  averaged  2.75  inches 
against  2.98  below. 

After  two  months  there  was  no  marked  difference  between  the  salmon 
in  the  lower  streams  and  those  above,  except  in  Hatchery  Creek,  where 
those  above  remained  very  small. 

At  the  end  of  four  months  the  average  length  of  the  salmon  was  3.35 
inches.  The  rate  of  growth  during  the  four  months,  taken  from  an 
average  of  all  the  salmon  retained,  was  .52  of  an  inch  per  month.  After 
four  months  this  rate  of  growth  fell  off  very  considerably,  and  at  the 
end  of  the  fifth  month  they  had  reached  an  average  length  of  only 
3.46  inches.  After  the  middle  of  the  sixth  month  no  more  seining  was 
done  in  the  streams  until  the  following  February,  or  eleventh  month, 
when  one  salmon  was  found  in  Olema  Creek  measuring  3.64  inches. 
On  April  14th,  thirteen  months  after  planting,  another  was  found  in 
Olema  Creek  4.45  inches  long.  One  other  was  found  in  Olema  Creek, 
of  which  I  have  no  measurements. 

Nearly  all  the  salmon  had  run  out  of  the  streams  by  the  end  of  the 
fourth  month,  and  those  remaining  after  this  time  were  evidently 
stunted  individuals,  as  is  shown  by  their  very  slow  growth.  An 
instance  proving  this  is  shown  in  the  following:  In  March,  5,000  of  the 


—  11  — 

fry  were  put  in  Bear  Valley  Creek,  which  is  dammed  at  its  lowest  end 
and  fixed  with  a  screen  so  that  the  fish  cannot  get  out.  Here,  eleven 
months  after  planting,  two  salmon  were  caught,  each  measuring  5.5 
inches.  At  the  same  place,  fifteen  months  after  planting,  two  speci- 
mens were  caught,  one  6  inches,  the  other  7.5  inches  long.  This  remark- 
able growth  in  a  stream  where  they  were, confined  is  another  point  that 
leads  to  the  belief  that  the  salmon  which  preferred  to  remain,  after 
four  months,  in  the  streams  where  they  were  not  confined  were  individ- 
uals stunted  or  the  physical  inferiors  of  those  running  out  during  the 
first  four  months. 

The  growth  of  the  salmon  was  the  same  in  Paper  Mill,  Nicasio,  and 
Olema  creeks,  but  in  Hatchery  Creek  the  growth  was  not  so  rapid. 
The  salmon  in  the  lower  end  of  the  creek  grew  rapidly  enough,  but 
those  above  grew  very  slowly,  gaining  on  an  average  the  first  three 
months  only  .15  of  an  inch  per  month.  At  the  end  of  the  fourth 
month  they  had  all  descended  to  the  lower  stream.  The  reason  of  this 
slow  growth  in  the  upper  stream  was  due  to  the  scarcity  of  food. 
Although  the  temperature  of  the  water  there  is  much  lower  than  it  is 
below  or  in  the  other  streams,  we  cannot,  knowing  what  we  do  of  their 
growth  in  other  cold  streams,  attribute  their  slow  growth  to  the  tem- 
perature of  the  water. 

Owing  to  this  difference  in  growth  in  the  same  stream,  the  variation 
in  the  size  of  the  individuals  is  great.  Out  of  thirteen  specimens  taken 
from  lower  Hatchery  Creek  at  the  end  of  three  and  one-half  months, 
the  largest  was  3.53,  the  smallest  2.26  inches,  a  difference  of  a  little 
over  1.25  inches;  or,  expressed  in  the  amount  gained  by  each  since 
planting,  the  largest  2.18  inches,  the  smallest  0.91  of  an  inch.  The 
variation  in  Olema  Creek,  where  no  difference  was  found  between  the 
upper  and  lower  stream,  after  the  second  month  was  nearly  as  great. 
From  seventeen  specimens  taken  at  the  mouth  at  the  end  of  three 
months  the  largest  was  3.42,  the  smallest  2.58  inches. 

The  important  points  learned  in  connection  with  the  rate  of  growth 
of  the  young  salmon  were :  First,  that  during  the  first  four  months 
their  growth  averaged  0.52  of  an  inch  per  month ;  Second)  that  the  few 
salmon  remaining  in  the  stream  after  four  months  were  stunted,  and 
grew  very  slowly  in  comparison  with  those  confined  in  Bear  Valley 
Creek. 

An  important  fact  to  be  noted  in  connection  with  the  salmon  confined 
in  Bear  Valley  Creek  is,  that  of  the  two  salmon  taken  in  February, 
1898,  both  were  males;  one  with  the  generative  organs  fully  developed. 
It  is  not  uncommon  to  find  young  4  to  4|  inch  male  salmon  remaining 
in  the  streams  with  the  testes  fully  developed,  but  it  was  never  before 
found  in  a  salmon  whose  age  was  known.  This  individual  found  in 
Bear  Valley  Creek  was  5.5  inches  in  length,  and  was  just  twelve  months 


—  12  — 

old.  It  should  also  be  noted  that  it  was  no  smaller  than  the  other  male 
salmon  taken  at  the  same  time.  Evidently  the  development  of  the 
sexual  organs  did  not  retard  its  growth. 

Although  these  young  male  salmon  are  occasionally  found  with  the 
generative  organs  prematurely  developed,  no  females,  to  the  best  of  my 
knowledge,  have  ever  shown  such  development.  This  premature 
development  peculiar  to  the  males,  accounts  for  the  undersized  males, 
or  u  grilse,"  accompanying  each  run  of  salmon  up  the  rivers,  and  it 
tends  to  prove  that  such  "grilse"  are  not  stunted  individuals,  but 
simply  that  they  have  matured  at  an  earlier  age  and  are  younger  than 
the  salmon  which  they  accompany. 

The  following  is  a  mere  speculation  in  regard  to  the  age 

THE  AGE      of  the  above  mentioned  "grilse":     We  have  already  seen 

OF  THE  that  one  out  of  the  two  males  taken  in  Bear  Valley  Creek 
"GRILSE."  at  the  age  of  one  year  was  sexually  mature.  In  the 
headwaters  of  the  Sacramento  we  have  in  November 
found  among  the  young  salmon  remaining  in  the  streams  several 
sexually  mature  males,  which  at  that  time  were  under  ten  months  of 
age.  These  few  examples  which  have  come  to  my  notice  represent  a 
very  small  percentage  of  the  number  that  must  mature  within  ten 
months  or  a  year  in  the  large  body  of  salmon  that  leave  the  stream 
immediately  after  hatching.  Reaching  maturity  they  would  naturally 
follow  the  next  run  of  salmon  up  the  river.  There  are  two  runs  of 
salmon  up  the  Sacramento  each  year  ;  the  fall  run  starting  up  the  river 
about  the  end  of  July  and  reaching  the  spawning  beds  at  Battle  Creek  in 
October.  The  eggs  spawned  by  this  run  hatch  in  January  and  February. 
Ten  months  after  hatching,  at  which  time  the  "grilse"  would  have 
matured,  would  be  too  late  for  them  to  catch  the  next  fall  run  up  the 
river,  but  they  could  catch  the  next  spring  run,  which  starts  up  the 
river  in  April,  and  reaches  the  spawning  grounds  in  the  McCloud  River 
in  June  and  July,  the  eggs  hatching  in  October  and  November.  The 
salmon  hatching  from  this  spring  run  get  out  of  the  river  in  time  for 
the  "grilse"  to  catch  the  fall  run  ten  months  later. 

If  this  is  true  the  "grilse"  running  in  the  spring  are  about  sixteen 
months  of  age  on  reaching  the  spawning  beds  in  June.  Those  arriving 
on  the  spawning  beds  in  the  fall  are  about  twelve  months  of  age.  If 
this  actually  happens,  the  "grilse"  of  the  spring  run  should  average 
larger  than  those  of  the  fall  run.  The  age  of  these  "grilse"  can  be 
determined  by  better  and  more  extended  observations,  and  such 
knowledge  would  be  a  long  step  toward  determining  the  important 
question  of  how  old  the  full-grown  salmon  are  whe*n  they  run. 


—  13  — 

The  young  salmon,  from  the  time  they  first  begin  to  feed, 
FOOD.        eat  almost  anything  they  can  get,  but  they  show  a  prefer- 
ence for  insects  and  insect  larvae,  and  they  prefer  to  cap- 
ture food  that  is  floating  on  the  surface  of  the  water.     An  examination 
of  the  contents  of  the  stomachs  of  the  young  salmon  taken  from  Paper 
Mill  Creek  and  its  tributaries,  from  the  time  they  were  planted  to  the 
time  they  reached  salt  water,  shows  that  their  food  was  almost  exclu- 
sively flying  insects  which  had  dropped  upon  the  surface  of  the  water. 

These  streams  abound  in  caddice  worms  of  three  or  four  species, 
small  periwinkles,  the  larvae  of  stone-flies,  may-flies,  and  other  insects; 
but  they  were  all  neglected  for  the  flies,  bees,  beetles,  caterpillars,  etc., 
that  fall  into  the  stream.  No  caddice  worms  or  periwinkles  were  found 
in  their  stomachs,  and  but  very  few  of  the  larva1  of  aquatic  insects. 
This  same  thing  was  observed  in  the  younger  trout;  and  although  the 
larger  trout  eat  large  quantities  of  caddice  worms,  the  insect  larvae  in 
the  water  do  not  furnish  the  amount  of  food  to  these  fish  that  is 
popularly  supposed. 

Although  these  salmon  live  almost  exclusively  on  insects  that  drop 
upon  the  water,  we  have  found  in  their  stomachs  pieces  of  leaves  and 
buds,  small  feathers,  shells  of  salmon  eggs,  and  the  helpless  young  of 
their  own  species.  (See  notes  on  planting  of  salmon  fry  before  yolk  sacs 
were  absorbed,  at  Sisson,  November,  1897.) 

In  the  salmon  taken  in  brackish  water  I  found  they  had  been  eating 
small  salt-water  crustaceans,  and  one  three-inch  salmon  taken  in  salt 
water  had  eaten  six  of  the  young  of  the  " silver  smelt"  (Atherinops 
affinis)  and  one  small  leaf-hopper  of  the  kind  that  is  found  among  the 
pebbles  along  the  shore  of  the  bay. 

In  almost  every  case  the  stomachs  were  filled  to  their  utmost  with 
food.  Tomales  Bay  abounds  in  small  crustaceans  and  the  young  of 
the  "silver  smelt,"  and  the  young  salmon  would  have  no  trouble  in 
finding  an  abundance  of  food  on  reaching  salt  water. 

Scarcely  any  vegetable  matter  was  found  in  their  stomachs,  and  what 
little  was  found  no  doubt  was  taken  by  accident. 

If  these  young  salmon  live  almost  exclusively  on  flying  insects,  the 
way  to  choose  a  good  stream  for  planting  would  be  to  select  one  with 
plenty  of  trees,  bushes,  and  grass  along  its  banks,  for  such  vegetation  is 
a  harbor  for  insects. 

The  principal  source  of  danger  to  young  fish  in  a  stream 

ENEMIES,     is  from  predaceous  fishes,  or  even  from  older  fish  of  their 

own  kind:     Of   the  four   species  of   fish  in  these   Harm 

County  streams — chub  (Rutilus  symmetricus) ,  stickle-back  (Gasterosteus 

cataphraclus) ,  blob  (Cottus  gulcrsas),  and  trout  (Salmo  gairdneri) — the 

last  two  only  are"  predaceous. 


—  14  — 

After  planting  the  young  salmon,  a  number  of  these  two  species  were 
caught  daily,  and  the  contents  of  their  stomachs  carefully  examined. 
Altogether  only  about  twenty-five  specimens,,  of  Cottus  gidosas,  of  size 
large  enough  to  prey  upon  the  young  salmon,  were  caught.  Out  of 
these  twenty-five,  not  one  had  eaten  a  fish  of  any  kind.  Thirty  or  forty 
specimens  of  Salmo  gairdneri  were  examined  daily  for  three  weeks  after 
planting,  and  in  not  one  instance  had  a  salmon  been  eaten.  The  only 
fish  eaten  by  them  was  Rutilus  symmetricus,  and  no  more  than  ten  of 
these  were  found  in  about  seven  hundred  examined. 

The  other  enemies  to  young  fish  observed  were  water  snakes,  king- 
fishers, herons,  and  divers.  Although  none  of  these  were  killed  to  find 
out  what  they  were  eating,  it  is  safe  to  say  that  the  loss  of  young  salmon 
due  to  them  was  slight. 

"PLANTING  OF  QUINNAT  SALMON  FRY  IN  MARIN  COUNTY  STREAMS  IN  1898. 

In  February,  1898,  2,000,000  Quinnat  salmon  fry  were  planted  in 
Paper  Mill  Creek  and  its  tributaries  by  the  United  States  Fish  Com- 
mission. On  account  of  limited  hatchery  space  and  lack  of  funds, 
the  fry  were  all  planted  before  the  yolk  sacs  were  absorbed.  The  fry 
hatched  at  the  same  time  as  those  liberated  in  these  streams  last  year, 
but  they  were  planted  about  three  weeks  earlier.  The  height  of  the 
water  in  the  streams  at  the  time  of  planting  and  during  the  next  month 
was  lower  in  1898  than  in  1897.  Notwithstanding  this,  the  salmon  ran 
out  earlier  than  the  year  before.  In  April  there  were  not  as  many 
salmon  left  in  the  streams  as  in  June  of  the  year  before.  In  June  no 
salmon  whatever  could  be  found  in  Paper  Mill  Creek.  Only  a  very  few 
were  found  in  Olema  Creek,  and  they  were  not  much  more  plentiful  in 
Hatchery  Creek — the  same  condition  that  existed  two  months  later  in 
1897.  The  only  reason  I  can  give  for  this  difference  in  time  of  running 
out  is  that  they  were  planted  at  different  ages.  Apparently,  planting 
before  the  yolk  sacs  are  absorbed  causes  them  to  run  out  earlier.  This 
brings  up  an  important  question :  Does  the  holding  of  the  fry  until 
after  the  yolk  sacs  are  absorbed  keep  them  from  running  out  as  soon  as 
they  would  under  natural  conditions  ? 

From  a  series  of  specimens  taken  in  April  and  June,  it  was  found 
that  their  average  growth  was  .52  of  an  inch  per  month.  It  should  be 
noticed  that  this  rate  of  growth  during  the  first  four  months  is  almost 
exactly  the  same  as  that  found  for  the  same  period  in  1897 — differing 
only  .05  of  an  inch. 


—  15  — 


NOTES  ON  THE  MOVEMENTS  OF  THE  YOUNG  OF  THE 
STEELHEAD  TROUT  (Salmo  gairdneri,  Richardson) 

IN  MARIN  COUNTY  STREAMS. 

By  N.  B.  SCHOFIELD,  of  California  Fish  Commission. 

The  steelheads  ascend  Paper  Mill  Creek  and  its  tributaries  regularly 
each  year  for  the  purpose  of  spawning.  Late  in  October  and  early  in 
November  they  appear  in  tide  water,  where  they  remain  until  the  first 
good  rains.  They  then  ascend  the  creeks,  and  spawn  on  the  gravel 
bars  in  December  and  January,  reaching  their  height  in  early  January. 

After  spawning  the  steelheads  drop  back  down  the  stream,  and  remain 
for  some  time  in  the  holes  in  tide  water  before  running  into  salt  water. 
Unlike  the  salmon,  they  do  not  die  after  spawning,  but  drop  back  into 
salt  water  and  return  to  spawn  again.  Steelheads  from  the  lower  Paper 
Mill  Creek  examined  in  April  after  spawning  showed  the  ovaries  with 
the  eggs  forming,  which  would  probably  have  matured  by  the  next 
winter  run. 

The  first  young  steelheads  appear  in  shallow  water  along  the  edges  of 
the  stream  after  absorbing  their  yolk  sacs  late  in  March,  but  they  do  not 
appear  in  any  great  number  until  late  in  April.  In  1897  they  began  to 
show  themselves  in  considerable  numbers  by  the  15th  of  April,  and  by 
the  25th  the  edges  of  the  stream  in  places  were  fairly  black  with  them. 
At  this  time  they  are  not  very  shy  and  are  not  frightened  when  one 
comes  near  them,  unless  his  shadow  chances  to  fall  on  them.  By  being 
cautious  one  can  with  his  hand  scoop  them  out  onto  the  bank.  This 
cannot  be  done  with  the  young  salmon  of  the  same  age,  as  they  are 
much  more  shy.  These  young  steelheads  as  they  lie  in  the  shallow  water 
kept  their  heads  against  the  current,  and  were  entirely  absorbed  with 
the  task  of  catching  something  to  eat — feeding  in  the  same  way  as  has 
been  described  in  the  case  of  the  young  Quinnat  salmon.  In  a  very  few 
days  they  left  the  shallow  water  and  moved  more  into  the  center  of  the 
stream,  where  there  is  more  floating  particles  of  food  for  them  to  catch. 

By  the  middle  of  May  nearly  all  the  small  steelheads  had  moved 
from  the  shallow,  quiet  water  along  the  edges  into  the  swift  water  near 
the  center  of  the  stream  or  into  the  deeper  holes. 

On  the  12th  of  June  the  average  length  of  the  young  steelheads  was 
taken  from  thirty-three  fish  measured,  and  was  found  to  be  2.6  inches. 
The  age  of  these  fish  we  can  estimate  very  accurately  to  be  fifty  days, 
counting  from  the  time  their  yolk  sacs  were  absorbed.  At  the  time  of 


—  16  — 

such  absorption  their  length  would  average  less  than  1.15  inches.  Thus, 
in  fifty  days  their  actual  gain  in  length  was  1.45  inches,  or  considerably 
over  three-fourths  of  an  inch  per  month.  This  is  even  a  more  remark- 
able growth  than  that  found  in  the  young  Quinnat  salmon. 

To  get  at  some  idea  of  their  abundance  I  will  copy  from  my  notes  of 
June  16,  1897,  on  seining  with  a  thirty-foot  net  in  upper  Olema  Creek: 
"The  first  haul  was  through  a  hole  thirty  feet  wide,  fifty  feet  long,  and 
three  feet  deep  in  the  deepest  place;  caught  61  young  steelheads,  27 
large  stickle-backs,  and  3  blobs.  The  second  haul  was  over  a  riffle 
with  pebbly  bottom;  hauling  about  thirty  feet  we  caught  25  steelheads 
and  10  stickle-backs.  The  third  haul  was  made  through  a  small  hole 
ten  feet  across  and  two  feet  deep,  with  roots  of  an  old  stump  at  the 
edge,  under  which  they  could  hide.  Here  we  caught  165  steelheads, 
7  stickle-backs,  and  10  blobs.  The  fourth  haul  was  through  a  hole  ten 
feet  wide,  fifty  feet  long,  and  three  feet  deep  in  deepest  place;  caught 
152  steelheads.  The  fifth  haul  caught  100  steelheads;  the  sixth,  75; 
the  seventh,  28;  the  eighth,  58;  and  the  ninth,  127  steelheads.  In  one- 
fourth  mile  seined  we  caugho  578  steelheads,  all  under  three  inches  in 
length.  I  have  estimated  that  we  took  two  thirds  of  the  steelheads  in 
that  distance.  There  are  twelve  miles  of  the  stream  in  which  they  are 
just  as  plentiful,  which  would  make  about  37,000  young  steelheads  for 
the  stream.  The  number  in  Paper  Mill  Creek  would  be  from  five  to 
seven  times  this  amount,  and  the  number  in  Nicasio  and  Hatchery 
creeks  would,  for  each,  be  about  one  fourth  the  number  in  the  Olema." 

"  Very  few,  if  any,  of  the  young  steelheads  have  moved  down  stream, 
and  nearly  every  one  to  be  found  in  Olema  Creek  now  has  been  hatched 
this  year." 

A  thorough  seining  of  the  streams  at  that  time  showed  that  there  was 
scarcely  a  steelhead  over  three  inches  in  length,  During  the  summer, 
when  the  water  is  low  and  warm,  the  steelheads,  except  those  hatched 
the  same  spring,  nearly  all  run  into  salt  water.  During  June,  while 
seining  for  young  salmon  in  brackish  water  near  the  mouth  of  Paper 
Mill  Creek,  young  steelheads  were  caught  in  considerable  numbers, 
ranging  from  5^  to  6^  inches  in  length.  In  all  the  red  colors  were  not 
lost  and  the  dark  bars  on  the  sides  were  bright  and  distinct,  showing 
that  they  had  just  come  from  the  upper  stream — for  the  bars  on  the 
sides,  and  especially  the  red  markings,  are  quickly  lost  in  brackish  or 
salt  water. 

After  the  first  good  rain  in  the  fall,  when  the  streams  begin  to  rise, 
the  young  steelheads  from  6  to  10  inches  long  appear  in  large  numbers 
in  tide  water,  with  their  sides  bright  and  silvery  and  the  dark  bar 
marks  almost  lost.  They  gradually  work  up  the  streams  and  soon  their 
color  gets  darker  and 'the  dark  markings  more  distinct.  After  each 
heavy  rain  there  is  a  fresh  run  of  these  steelheads,  and  as  the  water 
subsides  again  they  drop  back  into  salt  water. 


—  17  — 

There  is  the  best  of  evidence  that  these  fish  do  not  enter  the  streams 
for  the  purpose  of  spawning.  In  all  the  seining  done  from  January  to 
September,  not  one  steelhead  under  three  pounds  was  found  sexually 
mature,  and  none  were  found  that  showed  any  sign  of  becoming  so. 
By  questioning  people  resident  here  and  familiar  with  the  fish  in  these 
streams  I  find  that  small  steelheads  under  two  pounds  are  very  rarely 
if  ever  found  with  spawn. 

Rainbow  trout  (Salmo  irideus)  are  nearly  every  year  liberated  in 
Paper  Mill  Creek,  but  if  they  live  they  have  gone  back  to  the  habit  of 
running  back  to  salt  water  and  cannot,  in  habits,  general  appearance, 
or  structure,  be  distinguished  from  the  steelhead. 

Although  seining  was  done  in  tide  water  from  the  time  young  steel- 
heads  begin  to  hatch  until  the  14th  of  June,  none  of  them  were  caught. 
Up  to  this  time  they  had  not  begun  to  run  out,  but  they  did  run  out 
before  the  next  January.  They  probably  run  out  when  the  stream  is  at 
its  lowest,  late  in  August  and  early  in  September. 


2—s 


—  18  — 


NOTES  ON  AN  INVESTIGATION  OF  THE  MOVEMENT  AND 

RATE  OF  GROWTH  OF  THE  QUINNAT  SALMON 

FRY  IN  THE  SACRAMENTO  RIVER. 

By  N.  B.  SCHOFIELD,  of  California  Fish  Commission. 

Aided  by  the  knowledge  gained  in  the  study  of  the  habits,  move- 
ments, and  rate  of  growth  of  the  young  salmon  in  Marin  County,  we 
were  better  enabled  to  carry  on  the  more  difficult  work  of  finding  out 
the  movements  and  rate  of  growth  of  the  salmon  fry  in  the  Sacramento 
River. 

The  work  was  begun  in  the  headwaters  of  the  Sacramento  in  the 
neighborhood  of  Sisson  in  August,  1897,  and  has  been  continued  at 
intervals  to  the  present  time.  During  the  present  spring  the  United 
States  Fish  Commission  has  taken  up  the  same  work  in  the  Sacra- 
mento, and  in  the  following  report  I  have  made  free  use  of  some  of  the 
results  of  their  work,  especially  of  their  work  in  the  brackish  and  salt 
water  of  Suisun  and  San  Pablo  bays. 

To  make  clear  what  is  to  follow  I  will  explain  that  although  a  few 
salmon  may  spawn  in  some  of  the  tributaries  of  the  Sacramento  in 
almost  any  month  of  the  year,  the  vast  majority  of  them  spawn  at  two 
separate  and  distinct  times.  Eggs  deposited  by  the  spring  run  hatch 
in  October,  and  the  eggs  from  the  fall  run  hatch  the  following  Febru- 
ary. After  hatching  it  is  another  month  before  they  begin  to  swim 
around  and  feed. 

The  adult  Quinnat  salmon,  in  its  journey  up  the  Sacramento  for  the 
purpose  of  spawning,  never  reaches  Sulloway  Creek,  and  it  very  rarely 
reaches  a  point  as  far  up  the  Sacramento  as  the  mouth  of  the  Sulloway. 
The  young  Quinnat  salmon  found  in  the  Sulloway  and  this  part  of  the 
Sacramento  are  from  the  State  hatchery  at  Sisson,  and,  knowing  the  age 
of  the  fry  liberated,  it  is  possible  to  estimate  very  accurately  their  rate 
of  growth. 

On  August  28,  1897,  I  seined  Sulloway  Creek,  and  found  the  salmon 
fry  quite  plentiful.  To  better  illustrate  their  number,  in  one  haul, 
through  a  hole  three  feet  deep,  ten  feet  wide,  and  fifteen  feet  long,  I 
caught  twenty-seven  young  salmon.  In  other  parts  of  the  creek  they 
were  just  as  plentiful.  None  were  found  above  the  point  where  they 
had  been  liberated.  These  fry  had  been  planted  in  February,  and  at 
the  time  their  yolk  sacs  were  absorbed — about  March  10th — their  aver- 
age length  was  1.35  inches.  On  August  28th,  five  months  and  twenty 


—  19  — 

days  later,  they  had  grown  to  an  average  length  of  3.26  inches,  or  an 
actual  gain  in  length  of  1.91  inches;  an  average  gain  per  month  of  .33 
inch.  The  specimens  from  which  this  average  was  taken  contained 
the  smallest  and  largest  salmon  found,  or  2.83  and  4.08  inches,  between 
which  two  lengths  there  was  a  perfect  intergradation. 

On  November  2,  1897,  a  little  over  two  months  later,  Sulloway  Creek 
was  again  seined,  and  only  about  one  half  as  many  young  salmon  were 
found,  and  from  a  representative  series  ranging  from  3.30  to  4.18  inches 
in  length,  the  average  was  found  to  be  3.5  inches,  or  a  gain  of  .24  of  an 
inch  in  the  two  months. 

Early  in  November,  salmon  fry  hatched  from  eggs  taken  at  Baird,  011 
the  McCloud  River,  were  planted  in  Sulloway  Creek,  and  by  November 
22d  they  had  absorbed  their  yolk  sacs.  In  the  February  following, 
salmon  fry  hatched  from  eggs  taken  at  Battle  Creek  were  again  planted. 
These  absorbed  their  yolk  sacs  about  March  10th.  No  seining  was  done 
between  these  two  plants,  and  none  after,  until  the  15th  of  May,  1898. 
On  this  date  young  salmon  were  caught,  and,  after  measuring  a  larger 
series,  it  was  found  that  they  were  of  three  well-developed  sizes.  Those 
making  up  the  smallest  size  exceeded  all  of  the  others  8  to  1,  and  they 
had  grown  from  a  length  of  1.35  inches  on  March  10th,  to  2.18  inches, 
or  a  gain  of  .83  of  an  inch,  a  rate  of  .38  of  an  inch  per  month.  The 
smallest  salmon  found  belonging  to  this  group  was  1.64  inches,  the 
largest  2.8  inches.  The  next  size  ranged  from  3.58  to  3.9  inches,  and 
averaged  3.73  inches.  These  had  remained  in  the-  stream  since  the 
November  preceding,  and  there  were  very  few  of  them  as  compared  with 
the  smaller  size.  They  had  been  in  the  stream  nearly  six  months,  and 
showed  an  average  gain  of  .39  of  an  inch  per  month.  Only  two  speci- 
mens were  found  larger  than  this  size,  and  they  each  measured  4.6 
inches.  These  had  undoubtedly  remained  in  the  stream  at  least  since 
March  of  the  year  before. 

Although  it  had  been  only  a  little  over  two  months  since  several 
millions  of  salmon  fry  were  planted  in  this  small  stream,  there  were — 
compared  with  the  immense  number  planted — scarcely  any  left.  These 
observations  seem  to  warrant  us  in  drawing  the  following  conclusions: 
That  the  great  bulk  of  the  fry  planted  in  February  and  March  leave  the 
stream,  on  their  way  down  the  river  to  salt  water,  within  two  months;  a 
few  of  them  remain  until  the  rains  of  the  following  winter,  and  a  few 
individuals  may  even  remain  through  the  winter  up  to  the  beginning  of 
the  rains  the  next  fall.  Of  the  fry  planted  in  November,  nearly  all  leave 
the  stream  during  the  winter,  and  it  is  probable  that  they  do  the  same 
as  the  others — leave  the  streams  within  two  months.  I  should  add  that 
the  observations  of  the  young  salmon  in  Marin  County,  which  are  to  be 
found  in  a  separate  report,  and  the  subsequent  observations  carried  on 
in  the  Sacramento,  all  demonstrate  the  correctness  of  these  conclusions. 


—  20  — 

On  August  29,  1897,  I  seined  in  the  Sacramento  near  Sisson,  and 
found  salmon  ranging  from  2.63  to  4.37  inches  in  length,  with  an  average 
length  of  3.25  inches.  On  November  3, 1897,  I  seined  again  in  the  same 
place,  and  found  the  salmon  ranging  from  "3.25  to  4.50  inches,  with  an 
average  length  of  3.92  inches.  They  had  gained  .67  of  an  inch  in  the 
two  months  since  the  stream  was  seined  before;  or,  for  the  eight  months 
which  they  had  remained  in  the  stream,  an  average  gain  of  .32  of  an 
inch  per  month.  In  the  two  months  their  number  had  diminished  about 
one-half,  which  was  the  same  falling  off  as  found  in  Sulloway  Creek. 

On  November  6,  1897,  I  seined  the  upper  Sacramento  at  Sims,  and 
found  the  average  length  of  the  salmon  there  to  be  4  inches,  although 
they  ran  from  3.5  to  4.5  inches. 

On  May  17th  of  the  following  year,  a  little  over  six  months  later,  the 
stream  was  again  seined  at  the  same  place.  The  average  length  of  the 
young  salmon  at  this  time  was  2.67  inches,  although  they  ran  from  1.52 
to  3.76  inches.  In  this  series  the  fry  were  hatched  from  eggs  spawned 
by  two  different  runs,  which  accounts  for  the  great  difference  between 
the  largest  and  the  smallest  of  the  series.  Those  in  the  upper  end  of 
the  series,  and  which  average  about  3.5  inches,  had  absorbed  their  yolk 
sacs  and  begun  to  feed  six  months  before,  while  the  lower  end  of  the 
series  represents  those  which  had  begun  to  feed  only  two  months  before. 
If  two  hatches  of  salmon  as  young  as  these  and  with  such  a  difference 
between  their  ages  had  been  found  in  a  small  tributary  of  the  Sacra- 
mento we  could  expect  to  easily  separate  the  two  sizes,  but  in  the  main 
stream,  as  at  Sims,  where  the  young  salmon  are  from  several  different 
tributaries,  a  large  variation  in  the  size  of  the  individuals  occurs  and  it 
is  not  strange  that  the  two  sizes  cannot  be  readily  distinguished.  Out 
of  a  very  great  number  of  small  salmon  caught  here  the  largest  was 
scarcely  larger  than  the  smallest  taken  at  the  same  place  six  months 
before,  which  is  the  best  evidence  that  none  of  those  in  the  stream  six 
months  before  remained  through  the  high  waters  of  winter.  If  they 
had  remained  until  this  time  they  would  have  been  fifteen  months  old. 

In  Hazel  Creek,  a  tributary  of  the  Sacramento  near  Sims,  I  found, 
x>n  November  6,  1897,  two  sizes  of  young  salmon.  The  smaller  size 
varied  from  2.65  to  2.95  inches,  with  an  average  length  of  2.87  inches; 
the  larger  size  ran  from  3.93  to  4.42  inches,  with  an  average  of  4.19 
inches.  The  larger  size  greatly  outnumbered  those  of  the  smaller  size, 
and  agreed  well  with  the  size  of  the  salmon  in  the  Sacramento  at  Sisson 
and  at  Sims.  Of  the  smaller  size  only  four  were  taken.  Assuming 
that  they  had  grown  at  the  same  rate  as  the  others,  they  must  have 
hatched  from  the  egg  early  in  August,  and  allowing  three  months  for 
hatching,  they  were  spawned  early  in  May.  There  is  nothing  remark- 
able in  the  fact  that  salmon  spawned  here  in  few  numbers  at  that  time 
of  year.  The  first  salmon  of  the  spring  run  have  been  observed  passing 


—  21  — 

Baird  on  the  McCloud  in  April,  and  they  have  been  observed  spawning 
in  considerable  numbers  in  the  river  above  Baird  early  in  May. 
Although  the  spring  run  does  not  reach  its  height  at  Baird  until  late  in 
July,  a  good  many  salmon  arrive  earlier,  and  move  farther  up  the  river. 
The  number  of  these  irregular  salmon  is  so  small  in  comparison  with 
those  of  the  regular  spring  and  fall  runs  that  the  fry  resulting  should 
not  materially  affect  the  two  sizes  of  fry  hatched  by  the  spring  and  fall 
runs. 

On  May  17th  of  the  following  year,  after  the  winter  rains,  Hazel 
Creek  was  again  seined,  and  the  largest  salmon  found  was  2.82  inches, 
the  smallest  1.53  inches,  with  an  average  length  of  1.79  inches.  It  will 
be  seen  by  comparing  these  figures  with  those  of  fish  taken  six  months 
before  that  none  of  the  salmon  of  the  two  sizes  then  found  remained  in 
the  stream,  and  that  the  smaller  size  found  on  May  17th  were  hatched 
since  that  time  from  eggs  deposited  by  the  salmon  of  the  fall  run. 

In  the  first  week  of  September,  1897,  I  seined  the  lower  end  of  Battle 
Creek  thoroughly,  and  found  young  salmon  in  considerable  numbers 
running  from  3.08  to  4.58  inches,  with  an  average  length  of  3,58  inches. 
The  next  time  this  part  of  the  stream  was  seined,  on  December  5th,  it 
was  found  that  none  of  the  salmon  found  three  months  before  had 
remained  in  the  stream,  but  that  their  places  were  taken  by  a  new  lot, 
averaging  2.39  inches.  These  salmon  were  spawned  in  the  upper  creek 
by  the  spring  run,  had  absorbed  their  yolk  sacs  only  two  months  before, 
and  were  already  dropping  down  the  river  on  their  way  to  salt  water. 

At  the  United  States  and  State  hatchery  on  Battle  Creek  practically 
all  of  the  fall  run  of  salmon  entering  the  stream  were  caught  and  their 
eggs  taken.  Five  million  of  the  fry  hatched  from  these  eggs  were 
liberated  in  Battle  Creek  in  February,  1898.  They  were  liberated 
before  they  had  begun  to  feed,  but  it  was  estimated  that  their  yolk  sacs 
would  have  been  absorbed  by  the  10th  or  15th  of  March.  Mr.  Cloud 
Rutter,  of  the  United  States  Fish  Commission,  seined  the  lower  Battle 
Creek  on  April  30th  and  found  large  numbers  of  salmon  ranging  from 
1.40  to  3.45  inches,  with  an  average  length  of  2.13  inches.  This  shows 
a. gain  of  .45  of  an  inch  per  month  in  length.  Although  a  large  number 
of  salmon  were  found  in  Battle  Creek,  they  were  not  found  nearly  as 
abundant  as  they  should  have  been  had  all  the  immense  number 
liberated  remained  in  the  stream.  A  very  large  part  of  them  had 
unquestionably  drifted  into  and  down  the  main  river,  and  this  within 
a  month  and  a  half  of  the  time  they  began  to  swim  about  and  feed 
after  absorbing  their  yolk  sacs. 

On  April  28th  Mr.  Rutter  found  young  salmon  in  the  main  river 
,a,t  Red  Bluff  more  abundant  than  he  found  them  in  Battle  Creek  two 
days  later.  These  salmon  ran  from  1.51  to  3.09  inches,  and  had  an 
average  length  of  2.16  inches.  As  they  were  found  below  the  mouth  of 


—  22  — 

Battle  Creek,  and  their  size  coincided  within  .06  of  an  inch  of  those  in 
Battle  Creek,  and  in  view  of  the  fact  that  a  larger  number  of  the  salmon 
in  Battle  Creek  had  moved  out,  we  are  justified  in  saying  that  they 
came  out  of  Battle  Creek. 

On  May  4th  he  found  salmon  abundant  at  Redding,  ranging  from 
1.8  to  3.65  inches  and  averaging  2.38  inches.  On  May  5th  at  Tehama 
he  found  salmon  ranging  from  2.14  to  2.91  inches  and  averaging  2.53 
inches. 

Beginning  with  the  second  week  in  May  the  United  States  Commis- 
sion carried  their  investigations  into  the  lower  Sacramento  River  and 
into  Suisun  and  San  Pablo  bays.  In  the  second  week  of  May  young 
salmon  were  found  at  Collinsville  and  at  Benicia,  but  I  have  no  record 
of  their  number,  and  of  their  size  I  only  know  that  it  corresponded 
with  those  found  in  the  same  place  later  in  the  same  month. 

On  May  17th,  six  were  found  at  Pinole,  San  Pablo  Bay,  ranging  from 
2.4  to  3  inches  and  with  an  average  length  of  2.6  inches.  On  the  same 
day  one  was  caught  at  Point  Richmond,  San  Pablo  Bay,  3.31  inches 
long.  On  May  18th,  one  was  taken  at  Rodeo,  San  Pablo  Bay,  2.4  inches 
long.  On  the  20th,  23d,  and  24th,  five  were  taken  at  Benicia,  in  the 
strait  between  Suisun  and  San  Pablo  bays,  running  from  2.06  to  2.56 
and  averaging  2.29  inches  in  length.  On  the  30th,  three  were  taken  at 
Rio  Vista,  in  the  lower  Sacramento,  running  from  2.03  to  2.18  inches 
and  averaging  2.08  inches.  On  June  10th,  two  were  taken  at  Marshall's 
Landing,  near  Antioch,  the  largest  being  3.3  and  the  smallest  2.12 
inches  in  length. 

If  this  small  number  of  salmon  taken  in  salt  water  represents,  as  it 
unquestionably  does,  the  first  big  movement  of  young  salmon  out  of  the 
river,  it  at  first  appears  that  more  of  them  should  have  been  found,  but 
when  we  consider  the  vast  expanse  of  territory  the  lower  Sacramento 
covers  with  its  many  channels  and  bayous,  to  say  nothing  of  San  Pablo 
and  Suisun  bays,  it  is  not  so  strange  that  so  few  were  found — in  fact, 
the  strange  part  of  it  is  that  so  many  were  found— and  we  can  realize 
the  vast  number  that  must  have  distributed  themselves  in  these  waters. 

During  the  last  two  weeks  of  May  I  accompanied  Mr.  Rutter  on  a 
trip  down  the  Sacramento  in  a  row  boat.  Our  object  was  to  stop  and 
seine  the  river  at  every  available  place,  and  learn  the  abundance,  size, 
and  movements  of  the  young  salmon.  At  Redding,  on  May  18th,  we 
found  the  young  salmon  abundant,  with  an  average  length  of  2.43  inches. 
At  this"  place,  two  weeks  before,  their  average  length  was  2.38  inches. 
At  Red  Bluff,  on  the  20th.  we  found  no  salmon  whatever,  although  two 
weeks  before  they  were  very  numerous.  Just  below  Red  Bluff  we  found 
a  good  many,  their  average  length  being  2.16  inches.  From  here  to  a 
point  opposite  Chico  we  found  the  salmon  not  so  abundant.  In  a  haul 
with  our  fifty-foot  fine-meshed  net  we  usually  caught  from  twenty  to 


—  23  — 

thirty.  Below  Chico  this  number  fell  off,  and  we  caught  only  four  or 
five  in  a  haul.  At  a  point  two  miles  below  Knights  Landing  the  last 
salmon  was  caught,  although  we  seined  thoroughly  between  this  point 
and  Sacramento. 

Belqw  Red  Bluff  the  salmon  were  very  uniform  in  size,  averaging  2.4 
inches.  It  should  be  remembered  that  while  we  were  making  this  trip 
small  salmon  of  this  same  size  were  being  caught  in  salt  water.  They 
were  all  hatched  from  the  fall  run  of  salmon,  and  it  had  been  but  a 
little  over  two»  months  since  they  were  old  enough  to  feed.  Their  rate 
of  growth  after  the  absorption  of  the  yolk  sac  was  almost  .5  of  an  inch 
per  month. 

Early  in  July  Mr.  Rutter  again  made  the  trip  down  the  Sacramento, 
but  was  unable  to  find  any  salmon  whatever  below  Battle  Creek.  The 
run  of  small  salmon  out  of  the  river  had  ceased. 

The  conclusions  to  be  drawn  from  these  observations  are:  That 
immediately  or  very  shortly  after  the  salmon  are  old  enough  to  feed  and 
begin  to  swim  about  they  begin  to  drift  down  the  river,  and  within  two 
months  of  this  time  they  reach  salt  water.  By  the  end  of  the  fourth 
month  the  run  is  over,  and  those  remaining  in  the  headwaters  of  the 
river  stay  until  the  high  waters  of  the  following  winter.  The  number 
of  these  thus  remaining  is  small  compared  with  the  number  running 
out  immediately. 

The  rate  of  growth  of  the  salmon  during  the  first  two  months  after 
absorbing  the  yolk  sac,  taken  from  an  average  of  all  the  salmon  taken 
on  the  Sacramento,  was  .42  of  an  inch  per  month.  Those  remaining 
after  two  months  do  not  grow  so  fast.  Salmon  from  four  to  eight  months 
old  show  an  average  gain  per  month  of  a  little  over  .30  of  an  inch. 


YD  0443 


